How do scientists control the spread of disease?

Ecology can best be described as the study of what

Can someone give me the answers to this?

What is one affect on the australian environment due to the introduction of non-native european rabbits? (a) more grass grew in response to the need of the growing population of rabbits. (b) the rabbits balance out the food chain as they became a natural prey to many predators. (c) the rabbits the land by digging, which caused the soil to spread much needed nutrients. (d) the rabbits out-competed other small animals species and caused them to go extinct.